Final answer:
The equation of the line with a slope of 0 passing through the point (6, -8) is y = -8.
Step-by-step explanation:
When a line has a slope of 0, it means the line is horizontal. The equation of a horizontal line is of the form y = c, where c is the y-coordinate of any point on the line. In this case, the line passes through the point (6, -8).
So, the equation of the line with a slope of 0 passing through the point (6, -8) is y = -8.
Therefore, the correct answer is:
a) y = -8.
This equation represents a horizontal line along the y-axis at the y-coordinate of -8. The other options do not correctly represent a line with a slope of 0 passing through the given point.